Like suggested elsewhere, you can drag the magnifying glass into some plain text view. However, one can also directly drag it into a (rich text) email or chat message. Or into Google's search field which is conveniently close to Safari's location bar:
After dragging into Google's search field, Safari's location bar is still focussed. But in the search field only the URL is selected, hence easily copied when right-clicking that gray selection:
One could also first hit Tab after searching (to go into the search field), hit Delete to clear it, and then drag the icon. After that, the search field is ready for Command+C:
When using Messages (formerly known as iChat), the Share button at the left of the location bar can also share the URL:
As an aside: the Google URLs include a lot of irrelevant things, specific to your browser, language, etc. Often, it's enough to use www.google.com#q=elvis+is+alive, or for image search www.google.com#tbm=isch&q=elvis+is+alive, but then one needs to change the spaces into plus-characters to ensure it's clickable. (And one also needs to percent-encode other special characters.) It would be nice if Google would provide some bare sharing link on its own site.